Solar PV Panels

How does solar pv work?

Solar PV panels transform energy found in daylight, known as photons, into electricity. Solar panels are usually made up of a conductor material which in most cases is silicon. When the photons from the light hit the silicon a reaction occurs which creates an electric current. This current is then multiplied across the cells which form part of the panel.

This flow of electrical current can then be used in electricity across the home. Contrary to popular belief, solar panels do not need direct sunlight to work as photons are found in normal daylight. However, they are most effective in direct sunlight as there is a higher concentration of photons in this type of light. Presently, solar PV panels are not able to store any unused electricity to be used at a later date.

How Does Solar PV Work? (VIDEO)

The cost of solar pv

The price of Solar PV depends on several factors, the size, the system and the number of panels. All these factors will have a significant effect on the amount of electricity you produce and subsequently what your return on investment will be. The overall cost of Solar has fallen substantially in the past two years with the average system costing between £4k and £8k.

Use our solar calculator to discover what system is right for you: click here

The three main types of solar pv panel

There are three main types of solar panels, read about each of them below.

Monocrystalline

The most effective solar panels available today with efficiency levels of between 15-24%. They are also the most expensive as they are costly to produce.

Polycrystalline/Multicrystalline

The most cost-effective. They are a little less efficient than monocrystalline panels but much better than amorphous types with an efficiency of between 13-18%.

Amorphous/Thin Film Panels

Cheapest and least efficient of the systems, converting a maximum of around 8% of sunlight to electricity. However, they work well in overcast conditions and some can even generate small amounts of power on brightly moonlit nights. Their thinness and flexibility do make them more suitable for some applications. Inconsistent characteristics brought about but the varied chemistry used in their production makes their performance difficult to judge.

For more information on the different types of solar system and to find out what is the best for your home read What Solar System is Best?

Domestic solar panels

The Feed in Tariff has made a solar panel installation not only a smart environmental decision but also a smart financial decision for many homeowners. Coupled with the fall in solar panel costs it continues to be a viable option for many households looking to reduce their energy bills and earn an additional income.

There is limited criteria tha you have to benefit to benefit from a Solar PV installation, and the process can take as little as two weeks, from the moment you fill in the form, to the moment you are able to start earning with the FiT and saving on your energy bills.

Commercial solar pv

The Feed in Tariff applies to commercial installations as well as domestic. This means that you can use commercial space for Solar PV installations that will get you tax free earnings.Commercial properties are often the ones that can benefit the most financially from the FiT, they are also a fantastic opportunity for you to shout about your Green credentials.

If you own a commercial property, and are interested in a Solar Pv installation you can read more on Commercial Solar PV

Solar Roof Tiles

Used instead of traditional roof tiles, a solar tile system will cost more than solar panelling but will of course save you the money you would have spent on normal roof tiles when building a new home. Although this energy system is not as cost-effective, it’s an alternative solution where planning regulations deem solar panels inappropriate – for aesthetic or other reasons.

Used instead of traditional roof tiles, a solar tile system will cost more than solar panelling but will of course save you the money you would have spent on normal roof tiles when building a new home. Although this energy system is not as cost-effective, it’s an alternative solution where planning regulations deem solar panels inappropriate – for aesthetic or other reasons.

Efficiency considerations

Contrary to popular belief, solar panels do not need direct sunlight to work as photons are found in normal daylight. However, they are most effective in direct sunlight as there is a higher concentration of photons in this type of light. The electricity needs of the household and how much sunlight per annum can be expected in that location are some of the main factors to take into consideration.

The environmental and economical benefits of solar pv

The advantages

Environmental Factors

Solar PV panels create renewable energy because they do not use up any finite resources such as fossil fuels. The energy comes from a natural source which cannot run out. For this reason, solar PV panels are extremely good for the environment. There are also no harmful by products released during the creation of the electricity.

Financial Gain

The fact that the electricity from solar PV is created from natural daylight means that it is free. Whilst a household is using solar electricity they are not using mains electricity and, therefore, are not attracting a charge. It is estimated that an average domestic property with solar PV panels will save its owners around £80 to £100 a year on their electricity bills.

Whilst the above figure is nothing to be sniffed at, it hardly represents a major financial incentive, especially considering the cost of solar panels. However, this changed in 2010 when the British government launched the Feed In Tariff scheme. The scheme granted tariff payments to owners of renewable energy systems, including solar PV technologies, for the amount of energy that their system created.

In the example of solar panels, 43.3 pence was awarded for every unit of electricity that was created. Surplus electricity units, which were returned to the grid, were awarded an additional 3 pence. Over a year, an average domestic solar panel owner stood to make over £1,600 from these tariffs. The tariff payments were tax free and the tariff was guaranteed to last for 25 years. Solar PV owners stood to make a significant profit on the initial cost of installing the technology.

Cuts to the Tariff

The tariff was changed, however, and became less generous. After 1st August 2012 the Feed-In Tariff was cut down to 16 pence per unit - a full 63% cut from the peak seen in 2011. Furthermore, this tariff is only due to run for 20 years as opposed to the previous 25 years of the other tariffs.

The good news is that the cost of solar PV systems has fallen by around 50% in the past 18 months. This means the average homeowner can still enjoy an ROI of around 8-10% and can still expect to earn and save up £877 a year from the FiT and energy savings.

The disadvantages

Limitations of Solar Panels

Creating free electricity from solar panels sounds a great idea but, in reality, homeowners will still be dependent upon mains electricity. Solar panels are useless at night as surplus electricity generated in the day cannot be stored. Although solar panels still work in cloudy conditions, they are much less effective and often cannot create enough electricity to power a property. At this stage in their development, solar panels are unable to provide enough electricity all year round to displace the dominance of mains electricity.

The Cost of Solar Panels

Whilst the Feed In Tariff Scheme has made solar PV a good long term investment, this does not help with the initial cost. Although prices for solar panels have decreased and should continue to do so in the future, they are still expensive. Indeed, standard domestic systems cost anywhere from £5,000 to £8,000 to install. Even with the current Feed In Tariff rate, it will still take homeowners around a decade to make a profit. For many, this means solar PV is unattainable.

However, there are now solar loan products that help you get solar panels with no up-front cost. This means you can enjoy the benefits of solar without being out of pocket today.

Aesthetic Problems

Despite their increase in popularity in recent years many people still argue that solar PV panels are an eyesore. People claim that having the panels on the rooftop ruins the overall look of a house. Whilst this is a subjective viewpoint, homeowners may worry about how potential buyers of their property may feel about the panels should they choose to sell their homes in the future.

Solar PV is many people's vision for the future and judging by the Feed In Tariff Scheme it may well be the government's as well. Environmentalists see solar PV as a viable alternative to current electricity supplies because it does not use any fossil fuels and is a renewable and green energy creator.

The Feed In Tariff Scheme has attracted much media attention and, therefore, has awoken the pubic on the issue of solar PV. The scheme offers strong financial rewards to solar PV owners and this seems to have had a greater impact on sales than the environmental factor alone. To find out if solar is right for you please contact our Eco Experts today.

Maintenance of Solar PV

Your installer should give you details on all areas of maintenance before finishing installation, so ask about how to spot main inverter fault signals, and always ask for demonstrations where relevant. Mounted Solar PVs are more likely to need owner maintenance from time to time as they can gather debris that falls from the sky: bird droppings, snow, twigs and leaves to name a few. Warm soapy water and a soft brush should be used to clear your panels - speak to your installer for more advice, or ask your window cleaner whether they offer a panel cleaning service, as many do. Specialist window cleaners will have use of a water fed pole and tall brushes, so avoid taking the task into your own hands and leave it to the experts – it’s much safer this way and can be done affordably too.

Apart from keeping your solar panels clean and ensuring no shadow from overgrown trees, unmounted Solar panels require very little maintenance or upkeep. These panels are often tilted at an optimum gradient for allowing rainfall to roll off and clean the fronts. As long as you keep up to speed with the level of energy being generated from your Solar PV, you should be in a position to detect issues swiftly, should they arise.